Here's a small example, to show you the problems, not specifically with the NSA, but with anything "cloud". Let's imagine a malicious attacker is going after you...

Let's look at your gmail account. It's likely that you signed up for it with your old Hotmail account (the previously most common type of email service). Most people did. It's also likely that you protect your Gmail account fairly well, but have likely not changed your Hotmail password in a while. That's likely the best way in for an attacker.

Now, before you say "OK, but what's the risk", let's take a look at what information is accessible to someone getting into your Google account.

Firstly, they know the details of all your android devices (IMEI etc) - they know what tablets you have, what phones you have, and their serial numbers and identifiers. They can also carry out a remote wipe on any of your devices via Mobile Device Manager. Let's come back to this later though 

From Google Mail, they have a fair idea of what you're up to, based on your communications to other people. They can access your location history, and data-mine that, to figure out where you are. They can also look at your communications with other people via Hangouts and G+, and attempt to work out where you are (or simply use the GPS location). They can access the location sharing features of google's services, and see where you and your family are. They can see you're not at home (getting your address from an email), and go to your house, aware your kids are home alone, and rob the place, abducting them.

When you return home, you meet a scene of devastation. You take out your phone and call the cops. You call 911/999/112/whatever, but the call was intercepted and passed to the attackers, via software that was installed onto your phone remotely (via the play store's remote push system).

At this point, the attacker takes your phone, and puts you in the back of the van. He uses Google Device Manager, and removes the lockscreen password from your phone (via the forgot lockscreen code feature). This also resets your device encryption password to a known one. At this point, all the devices are turned off, and their SIMs removed, and you are driven to a remote location.

The attackers then call your partner (having got their number from your Google contacts), and demand $1 million, while telling your partner that you know they are currently in <name of place from their google shared location feature>. The same remote access toolkit is installed onto their phone (given they had used your email as a recovery email for their Google account), and this permits monitoring of their phone to check if they call 911 etc. 

OK, that all sounds far-fetched, but that is all entirely possible. The sheer amount of data being held about you, by google and other cloud providers, is insane. I didn't even go into the possibility of financial theft here. Cellphones are a very important thing to people, and they often take them for granted. Would you consider that when you called 911 in a moment of need, that someone had remote-installed a piece of malicious software, which exploits an android security hole, to replace the dialer app, and route the call to a rogue attacker, pretending to be the emergency services?

The amount of control that "other people" have over a phone running "Google Apps" is immense. Don't just think about the "NSA" aspects of this - consider how devastating it would be if someone had access to your Google account. And now remember that anyone on the technical team of Google could (in theory) issue an access token to your account to a well-paying attacker...

Oh, and one of the best ways an attacker can get into your Google account is simply to steal a phone or tablet, and extract the Google authentication token. Sure, they might not be able to change your password, but they are now "into" the chain, and will be able to start the attack.

If this don't bother you, I don't know what will...